Machine for manufacturing couplings



No. 689,203. Patented Dee. I7, I90I.

n. A. umkm.

IAGHIIIE FUR MANUFACTURING BUUPL'IIIGS.

(Anuncian and lov. 14, moo.)

f Patentd Dec. I7, |90I.-

D. A. LANKIN. MACHINE FUR MANUFACTURING COUPLINBS.

(Application mad Nov. 14, 1900.) l

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' un. 689,203. rammed uw. n, |901- n. A. I Anxm. Y MACHINE FOR MANUFACTURING COUPLIIIGS.

(Application llsd Nov. 14, 1900.) l

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No. 689,203. Patented nu. I7, 19m;-

u. A. L'Anxm. IAGHINE FUI IAIIUFICTURIIIG COUPLINGS.

(Anuncian nua lov. 14, woo.)

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UNITED STATES PATENT OFFICE.

DAVI'D-A. LARKIN, OF PITTSBURG, PENNSYLVANIA.

MACHINE FOR MANUFACTURING COUPLINGS.

SPECIFICATION forming part of Letters Patent N o. 689,203, dated December 17, 1901.

Y Application led November 14, 1900. Serial No. 33,467. (No model.)

To all whom it may concern:

Be it known that I, DAVID A. LARKIN, a citizen of the United States of-America, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in vthe Manufacture of Couplings and Unions, of which the following is a specification, reference being had therein to the accompanying draw-` ings.

This invention relates to certain new and useful improvements in the manufacture of couplings and unions, and has for its object the provision of novel means whereby a coupling or union is both welded and threaded in one operation.

Another object of the inventionis to form, weld, and thread a pipe coupling or union without removing or shifting the blank from which it is formed until the work embraced in the forming, welding, and threading has been completed.

The invention further aims to construct a machine wherein a coupling or union may be easily removed when completed, leaving the machine in a position to receive a blank to form, weld, and thread the next coupling or union.

With the above and other objects in View the invention consists in the novel machine for forming a coupling or union to be hereinafter more fully7 described, and speeically pointed out in the claims.

In describing the invention in detail reference is had to the accompanying drawings, forming a part of this specication, and wherein like numerals of reference indicate corresponding parts throughout the several views, in whichy Figure l is a front elevation of an apparatus suitable for the manufacture of couplings, unions, &c., in accord-ance with my invention. Fig. 2 is a similar view, partly in vertical section. Fig. 3 is a side elevation thereof. Fig. 4 is a similar view, partly in vertical section. Fig. 5 is an enlarged perspective view of the lower die. Fig. 6 is a similar view of the hinged upper die. Fig. 7 isfa vertical sectional view of the nished coupling or union. Fig. 8 is a detail plan view of a part of the blank, showing how the ends of the same are cut.

The ordinary coupling .or-union as now l made is either cast in a mold and then thread- 'ed'to some standard gage or is formed from slab iron or steel welded over a mandrel and then threaded, requiring much handling and shifting about from one machine to another. WhenA such couplings are made in the mold from cast-iron, they must either be annealed before the metal has cooled or settled or be made very heavy in order to resist the strain vthey are subjected to when used for uniting the ends of pipe. One purpose of this invention is to take an ordinary blank of wroughtiron or steel, cut, as formerly, from a plate of the vrequired thickness, heat the same to the welding heat, and wrap it around a threaded mandrel or pair of mandrels, as shown in the drawings, welding the edges of the blank and at the saine time forcing the metal into the screw-threads of the man drels to form the thread on the interior of the coupling or union. After the coupling or union has been formed the mandrel `or inandrels. are withdrawn and the finished coupling or union removed from the mold.

It is 'claimed that in the formation of any metal body from highly-heated metal the surface, face, or that part of the metal coming in contact with the roll, mold, chill, or core is harder and more resistant and is much stronger than if reduced to shape by cutting. It is the object of lny invention to not only secure a more perfect thread, but to leave the fiber of the metal intact by compressing themetal whilein a heated'state, so as to form the threads of the coupling or union, leaving the finished article all the strength ythe metal contained beforethe threading was attempted.

" It is a well-known fact that the welding ofv `metal along a straight line, whethery butt or lap weld, is much more easily fractured or impaired than where the weld is made along irregular lines, so that in forming a coupling or union in accordance with my invention I preferably cut the edges of the blank on irregular lines or on a line of inclines or angles forming screw-threads, the ends interlocking with each other and being also forced into the screw-threads on the mandrel or mandrels and conformingto them while in the process of welding.

IOO

While various forms of machines may be constructed for carrying out my invention, I have herein shown a practical form of apparatus and will now describe the same brieiiy.

l indicates a base-plate which supports suitable housings 1. In these housings are arranged the oppositely-screw-threaded man drels 2, provided on their outer ends with pulley-Wheels 3. A lower die et is mounted on the base-plate between the two housings and is ,provided with a concave upper face 5, in which the one half of the coupling or union is formed. Operating in connection with the lower half of the mold is an upper section or half which is constructed of two equal members or sections 8, cach of which carries apertured lugs 9 forpivotally connecting by a pin or like means to apertured lugs 6, carried by the lower half of the mold or die. Each lmember or section ofthe upper mold or die is also provided with upwardly-projecting arms 10, having apertures 11 to receive a pin 12 for connecting the arms 10 to the lower ends of the levers 13, the latter being pivotally connected at their upper ends to piston-rods 14 of pistons (not shown) which operate in suitably-arranged cylinders 15. The mandrels operate through the e'nds of the mold or die, the lower part 4 being suitably recessed, asat 7, to receive the said mandrels. They may be operated to drive the same into the mold or die or withdraw the same therefrom by a suitably-driven belt 18 or in any other desired manner. The mandrels are slightly tapered at their free ends, as shown, so that the threads 17in the iinished coupling or union 16 will taper from the center toward each end, a's shown in Fig. 7. l

In Fig. 8 I show a portion of the blank 16', from which the coupling or union is formed, illustrating how the ends 17 are cut on-irregular lines to form a more substantial weld. To produce a finished coupling or `union with an apparatus such as described, the blank 16 is first heated to the fusing-point and then placed in the lower section or member/lf of the die or mold. The mandrels 2 are driven into the mold until the ends of the same abut, ywhen air is admitted to the cylinders to operate the pistons and actuate the levers 13, closing the sections or members 8 of the upper mold orA die upon the blank, wrappin g the latter around the threaded mandrels, and at the same time compressing the sameinto the threads of the mandrels, so as to form the. threads of the coupling or union, and also by this compressionrwelding the serrated ends of the blank together. When the coupling or union has been vthus formed, the mandrels are` Unthreaded from the coupling or union, the levers are operated so as to open the upper part of the mold or die, and the finished coupling or union may then be removed, another blank placed in the die or mold, and the operation repeated. It will be noted that by this means a simultaneous welding and threading of the tube, coupling, or

union is effected without shifting or handling of the same'after the blank for the-.same has .been placed in the machine without further labor than to revolve the mandrels to drive the same into the mold and then to withdraw n the same from the mold to permit the removal of theinished article. If desired, the simultaneous welding and threading may be accomplished by employingin lieu of the hinged upper die a roller or set of rolls made to re- -volve around the threaded mandrels to compress ihe heated metal,.or a plain mandrel could be employed for wrapping the blank around the same to weld the same into tubular form, and the plain mandrel then withdrawn and the threaded mandrels inserted to form the threads. Such an operation might be advantageously employed in the manufacture of sleeves for lead joints, though generally the two threaded mandrels around which the blank is wrapped will be employed, the purpose in employing two beingto facilitate the working and enable the operator to Withdraw the mandrels in half the timenecessary to withdraw a mandrel the length of which equaled the outside lines of Athe coupling or union.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a device of the character described, the combination with a pair of rotatable and longitudinally-movable threaded mandrels,

of a lower die or mold adapted to receive a heated metal blank, the said mandrels operating through the ends of said die or mold, an upper die or mold comprising two sections each of which is pivoted to the lower die or IOO mold, and means connected to the sections of the upper die for closing the same upon the mandrels after the latter have been driven into the lower die or mold, said sections of the upper mold in their closing action engaging the heated blank to weld the edges thereof andcompress the blank on the mandrel, substantially as described.

2. Ina device of the character described,

the combination with a pair' of rotatable and' longitudinally-movable threaded mandrels,- of a die ormold adapted to receive a heated metal blank, said mold or die comprising a stationary lower section and anrupper section comprising two equal members which are pivoted to the stationary lower section, and means connected to the pivoted members to close the same to bring the edges of the blank together and weld said edges and to compress the blank upon the mandrels for simultaneously threading at the time of Welding, substantially as described.

3. In a machine of the class described, the combination with a rotatable and longitudinally-movable threaded mandrel, of a die or mold adapted to receive a heated metal blank for welding and simultaneous threading, said die or mold comprising a stationarylower section into which the heated blank is first placed,

and pivoted upper sections adapted to wrap the blank upon the mandrels, and means connected to the pivoted sections of the die or mold for actuating the same to wrap the blank upon the mandrel to simultaneously weld and thread the same, substantially as described. 4. In a machine of the class described, the combination` with a pair of rotatable and longitudinally-movable threaded mandrels mounted in alinement with each other and movable toward and away from each other, of a'die or mold adapted to receive a heated metal blank, said die or mold comprising a stationary section and two movable sections pivoted to the stationary section, and means for operating the movable sect-ions to wrap the heated blank upon the mandrels and simultaneously weld. and thread the same, substantially as described.

blank is placed, and movable sections pivoted to the stationary sections for engagement with the blank, and means for operating the movable sections of the mold for wrapping the blank upon vthe mandrels to com- 4press and weld said blank, substantially as described.

In testimony whereof I affix my signature in the presence of two witnesses.'

DAVID A. LARKIN. Witnesses:

JOHN NOLAND, E. E. POTTER. 

